Field of the Invention
The present invention relates to an image processing method which performs pattern matching processing with the use of a reference image, an image processing apparatus, a robot apparatus, a program, and a recording medium.
Description of the Related Art
An image processing apparatus which performs pattern matching processing with the use of a reference image in a searching region that is set on an input image to detect a work position on the input image, and a robot apparatus provided with the image processing apparatus are widely used.
In the pattern matching processing with the use of the reference image, the image processing apparatus repeats a calculation of shifting the position and angle of the reference image little by little in the searching region that has been set on the input image, and determining the evaluation value of the pattern matching. Because of this, if the searching region is large, an amount of calculation becomes enormous, and a calculating time is extended before the work position on the input image is determined. In addition, in order to enhance the precision of the pattern matching processing with the use of the reference image, it is necessary to reduce an increment width of the position and inclined angle at which the pattern matching processing with the use of the reference image is performed in the searching region. In addition, also in the case where the increment width of the position and inclined angle is made small at which the pattern matching processing is performed in the searching region, the amount of calculation becomes enormous, and the calculating time for the work position on the input image to be established is extended.
Then, in Japanese Patent Application Laid-Open No. 2003-60888, the image reading apparatus performs pattern matching processing by using the reference image in a strip-shaped searching region which has been previously set on the input image based on an imaging rule of the input image, and thereby reduces the amount of calculation in the pattern matching processing.
In addition, in Japanese Patent Application Laid-Open No. 2011-43922, the mobile-object recognizing apparatus continuously images a mobile object, estimates the position of the mobile object, and performs the pattern matching processing by using the reference image in the searching region which regards the estimated position as a center, and thereby reduces the amount of calculation of the pattern matching processing.
There is the case where the work positions in the input image of a work held by a holding unit imaged by an imaging unit appear preferentially in a plurality of distributed regions on the input image. In this case, if the pattern matching processing with the use of the reference image is performed on all of the work positions in the searching region, as are described in Japanese Patent Application Laid-Open No. 2003-60888 and Japanese Patent Application Laid-Open No. 2011-43922, pattern matching processing results in being executed many times, which has no possibility of detecting the work position, in a region among the plurality of distributed regions.
The present invention relates to: an image processing method which can reduce an amount of calculation in pattern matching processing with the use of a reference image, in the case where work positions to be detected on an input image appear preferentially in a plurality of portions; an image processing apparatus; a robot apparatus; a program; and a recording medium.